Steam-g-eneratob



J. JOHNSON,

STEAM GENERATOR.

Patented Oct, 9, 1860.

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I I m UNITED STATES PATENT OFFICE.

JOHN JOHNSON, OF BIDDEFORD, MAINE.

STEAM-GENERATOR.

Specification of Letters Patent No. 30,326, dated October 9, 1860.

To all whom it may concern:

Be it known that I, JOHN JOHNSON, of Biddeford, in the county of York, and State of Maine, have invented a new and Improved Combined Steam Generator and Superheater; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawing, forming partof this specification, in which Figure 1 is a side view. Figs. 2, and 3, are vertical sections at right angles to each other.

Similar letters of reference indicate corresponding parts in the several figures.

To enable others skilled in the art to make and use my invention I will proceed to describe its construction and operation.

A, represents the water casing made of quadrangular form in its horizontal section. This casing has in the front openings a and b, for the fire-door and ash-pit, and has at one end openings 0, and (Z, for the upper and lower tiers of the generating and superheating tubes. The space surrounded by this casing opens at the top into the chimney which is situated above the said casing but is not represented in the drawing, and the lower part of the said casing contains the fire grate.

B, B, are the steam generating and superheating tubes arranged in horizontal tiers connected at their ends, within the space that is surrounded by the casing, by means of square joints or double elbows e, c, in such manner that each tube of the lower tier is connected by intermediate tubes in a vertical range with a corresponding separate tube of the upper tier independently of all the other tubes. The tubes of the lower tier are situated at such a distance above the grate as to allow room for combustion be low them. The tubes of the upper tier are all connected outside of the casing A, with a pipe C, by which to supply them with heated water from the casing A. This pipe O, is intended to be connected with the feed pipe of a steam pump or pump operated by the engine whose suction pipe is connected with the Water casing A. This pump is not represented, but the connection of its suction pipe with the water casing is shown at D, in Fig. 1.' The tubes of the lower tier are all connected outside of the casing with a pipe E, by which the superheated steam is to be conveyed to the engine or other apparatus in which it is to be used. The tubes B, B, are severally furnished near their c011- nections with the pipes'C, and E, with stop cocks or valves f, f, to shut off any that may be out of repair.

F, is the feed pipe of a pump for supplylng water to the casing A, to be heated therein preparatory to its being supplied to the tubes B, B.

G, is the suction pipe of a hand pump which is to be connected with the casing A; and pipe O, for the purpose of supplying water from the casing to the tubes B, B, until the steam is up to sufiicient pressure to start the steam pump or engine.

H, is a pipe connected with the casing near the top thereof and having two branches one for the purpose of carryingoff any undue quantity of water that may be fed into the casing A, and the other for conveying to the chimney or to a condenser, or other place any small quantity of steam that may accidentally be generated in the casing, in which the water is not intended to be heated above the boiling point.

It will have been understood from the foregoing description of the construction that the water in the casing A, which constitutes a heater is not subject to the pressure of the steam and that two feed pumps are necessary to keep the generator or superheater in operation the one to pump the water into the casing and the other to pump it from the casing into the pipe C, for the supply of the tubes B, B. The operation of these pumps requires to be regulated so that the casing A, is not overflowed and that the tubes are supplied from the said casing no faster than the steam is generated and used. The lower tubes B, B, are heated by radiation from the incandescent fuel on the grate and all of the said tubes are heated by the circulation between among and around them of the flame and heated gaseous products of combustion, the lowest tubes being heated most intensely and those above gradually less according to their distance from the tire. The water fed to the pipe C, gradually overflows the said pipe to the upper tier of tubes B, B, from whence it circulates through the several tiers till converted into steam. ters the upper tier of tubes it is expanded and it is dashed against the square joints at WVhen the water en-- the ends of the said tubesand converted into wet spray and steam in, which condition it passes through the next tier of tubes with.

increased velocity and so on from one tier to another till before it arrives at the lower tier it is all converted into steam, and after this conversion has been completed it.be-,

comes superheated in passing onward to the pipe E. v

I do not claim broadly the generation of steam for forcing water into one end of a heated coil or serpentine arrangement of pipes or tubes in such quantity that all will be converted into. steam before its arrival at the outer end :V1But p r c 15 What I claim as my invention and desire to secure by Letters Patent is The arrangement of the tubes B, and valves f, with each other and with the independent water heating case A, in the man- 20 ner herein shown and described.

Fri

JOHN JOHNSON.

Witnesses: S. HENDERSON,

ROBERT SPLAINE. 

